J. Kissel, E. Capote, J. Betzwieser

Today, I turned OFF the 1153.2 Hz PCALY Calibration Line by changing the frequency and amplitude to 0.0, and turning off the corresponding element in the OSC SUM matrix. 
    $ caput H1:CAL-PCALY_PCALOSC9_OSC_FREQ 0.0
    $ caput H1:CAL-PCALY_PCALOSC9_OSC_SINGAIN 0.0
    $ caput H1:CAL-PCALY_OSC_SUM_MATRIX_1_9 0.0

I've saved those settings in the OBSERVE / safe.snap SDF files to make that stick (they're the same file, soft-linked together).

Context
This line has been on consistently throughout O4, at the same frequency with no change in amplitude -- but never used for any science; t'was just eating up PCAL range. And now the REST of the story... In O3, the PCAL team began prototyping a constant comparison between PCALX and PCALY in order to determine \chi_{XY} . On Sep 11 2019, we turned on a line at 1153.1 Hz
at both end-stations with opposite sign forming a "canceling line" (LHO:51915). Realizing that a truly canceled line has no SNR above the DARM noise to make any statistically significant statement, they moved to 395.1 Hz for a minute (LHO:53259). Then, they finally tried separating them near the end of O3 at 1153.1 and 1153.2 Hz lines on PCALX and PCALY respectively (LHO:54876). Finding they still needed more SNR, they moved the comparison briefly down to 530.2 and 530.1 Hz (LHO:54868); this became the final measurement for P2000113), and then returned them to former frequencies of LHO:54868 on 2023-03-03 (LHO:55386)... and then we just never turned off the PCALY portion #globalpandemicwhoops. The corresponding PCALX portion, at 1153.1 Hz, was unceremoniously turned off without aLOG on a Thursday afternoon between O3 and O4, at 2022-12-08 22:29 UTC (14:29 PDT).